The present embodiments relate to an economical and environmentally friendly method for obtaining distilled waxes from recycled polyethylene.
Wax is used in large quantities for various manufacturing processes, and represents a large cost of supplies for companies using such processes. For example, in the printing industry, wax is a critical component which represents a substantial portion of both toners and inks. Moreover, in many of these processes, the wax used is expensive distilled wax. Distilled waxes are expensive because the raw material feeding the distillation process is scarce and a great deal of the wax feed is wasted in the distillation process.
Thermal degradation of high molecular weight polyethylene has been ongoing for decades. The primary goal of previous work, occurring mainly in academia, was an attempt to elucidate degradation mechanisms and generate materials which were primarily very low molecular weight hydrocarbon fuels. There has been very little concerted effort in the area of degrading polyethylene (PE) so as to obtain a PE-wax suitable as a raw material for other processes.
Most if not all methods for producing PE-waxes from high molecular weight PE feed stocks include thermal degradation through pyrolysis. However, these methods are not suitable for producing high quality waxes for certain applications, such as making toners or inks because they only perform a degradation step. Since the amount of degradation is difficult to control, the resulting material has a wide molecular weight distribution resulting in a material with a broad melting range which is undesirable. The distillation step is necessary for producing a narrow molecular weight distribution which in turn results in a material with a sharp melting point.
Thus, a new route for the production of distilled wax that can be used as a raw material for other processes and that is efficient and cost effective, for example, uses less expensive feedstocks, is highly desirable.